A Fin Field Effect Transistor, also known as a FinFET, is a type of non-planar or three dimensional transistor used in the design of modern processors. As in earlier, planar designs, it is typically built on an SOI (silicon on insulator) substrate. However, FinFET designs also use a conducting channel that rises above the level of the insulator, creating a thin silicon-based structure, shaped like a fin, which is called a gate electrode. This fin-shaped electrode allows multiple gates to operate on a single transistor. FinFET devices also have significantly faster switching times and higher current density than the mainstream CMOS technology.
There is an ongoing need for new FinFET designs. Specifically, there is a need for new materials and surface compositions to allow for an expanding set of design options. Selective deposition has shown promise as it has the potential to allow for the deposition of films on select surfaces and simplify integration schemes.
Selective deposition of materials can be accomplished in a variety of ways. For instance, some process may have inherent selectivity to surfaces just based on their surface chemistry. These processes are fairly rare and usually need to have surfaces with drastically different surface energies, such as metals and dielectrics. In FinFETs, and other cases where surfaces are similar (e.g. SiO2 versus SiN), the surfaces need to be selectively blocked by employing surface treatments that selectively react with one surface and not the other, effectively blocking any surface reactions during a subsequent deposition process. Yet, some deposition precursors are not effectively blocked by current technologies.
Therefore, there is an ongoing need in the art for methods and materials to inhibit deposition on certain surfaces while selectively depositing films on other surfaces.